Reduce sleep latency -- i.e. the time it takes you to fall asleep!
Increase 'alpha waves' for increased relaxation- during the first stage of sleep (N1) when you're just beginning to drift off.
Naturally lower your 'stress hormone levels (i.e. cortisol) - reducing feelings of stress, racing thoughts and anxiety. Quieting your mind, so you relax into sleep!
Inhibit the drive for wakefulness from your circadian pacemaker - so you don't wake up too early!
Noticeably increase the quantity of restorative sleep you get each night - so you wake up feeling energised, refreshed and alert.